Form resource not found after on-the-fly String-Resource translation - forms

Question

I have a problem which occurs only in a very small customer range and I would like to ask if you might give me a hint where the problem might be. The program works for 98% of the customers. Alas, it is not possible that I work with the customers to debug the issue, because their knowledge of Windows and computers is very basic. It is also not possible that I send multiple versions of the product to them, since they don't even know how to install software (the admins do all the stuff).
First of all, I translate all RT_STRING resources on-the-fly, so that the language-switching in the program also affects hardcoded stuff like "Yes", "No", "Cancel" etc., which would only be possible by compiling 2 EXE files.
The code (I have tried to left away as much unnecessary stuff as possible, but since I don't know where the problem is, I provided as much details for the bug as possible):
The ony-the-fly resource translation
procedure TranslateResources;
var
i: integer;
s: string;
{$IF NOT Declared(FILE_ATTRIBUTE_NOT_CONTENT_INDEXED)}
const
FILE_ATTRIBUTE_NOT_CONTENT_INDEXED = $2000;
{$IFEND}
begin
// I copy all resources in a dummy DLL (without code), because
// 1) The resources are the only thing we need when changing the resource module
// 2) If the EXE code/debug sections are too long, BeginUpdateResource() will ruin the performance heavily
FTempFile := IncludeTrailingPathDelimiter(GetTempDirectory) + GetRandomString(8)+'.dll';
// Transfers all resources from ParamStr(0) into the dummy DLL at FTempFile
ReGenerateResourceFile(FTempFile);
// if necessary, remove readonly flag
SetFileAttributes(PChar(FTempFile), FILE_ATTRIBUTE_OFFLINE or
FILE_ATTRIBUTE_NOT_CONTENT_INDEXED or
FILE_ATTRIBUTE_TEMPORARY );
for i := 0 to Length(RTLResStringTranslationArray)-1 do
begin
s := Translate(RTLResStringTranslationArray[i].TranslationID);
if s <> '' then
begin
// Translate the string
UpdateResString(RTLResStringTranslationArray[i].ResStrDescriptor.Identifier, s);
end;
end;
LoadNewResourceModule(FTempFile):
end;
procedure ReGenerateResourceFile(OutputFile: string);
var
hUpd: Cardinal;
rs: TResourceStream;
fs: TFileStream;
begin
// As template we use a dummy DLL which contains no code.
// We will implement all resources from ParamStr(0) into it, before we translate the strings.
rs := TResourceStream.Create(HInstance, 'DUMMYDLL', 'DLL');
fs := TFileStream.Create(OutputFile, fmCreate or fmOpenWrite);
try
fs.CopyFrom(rs, rs.Size)
finally
rs.Free;
fs.Free;
end;
// Transfer resources from our EXE into the dummy DLL file
hUpd := BeginUpdateResource(PChar(OutputFile), true);
try
EnumResourceTypes(hInstance, #_enumResTypesProc, hUpd);
finally
EndUpdateResource(hUpd, false)
end;
end;
// This is based on reinit.pas from Borland's RichEdit example; slightly modified
function LoadNewResourceModule(PatchedFile: string): LongInt;
var
NewInst: Longint;
CurModule: PLibModule;
begin
Result := 0;
// Win95: "Initialization routine failed"
// NewInst := LoadLibrary(PChar(PatchedFile));
NewInst := LoadLibraryEx(PChar(PatchedFile), 0, LOAD_LIBRARY_AS_DATAFILE);
CurModule := LibModuleList;
Result := 0;
while CurModule <> nil do
begin
if CurModule.Instance = HInstance then
begin
if CurModule.ResInstance <> CurModule.Instance then
FreeLibrary(CurModule.ResInstance);
// Win95: ERangeError
CurModule^.ResInstance := NewInst;
Result := NewInst;
Exit;
end;
CurModule := CurModule.Next;
end;
end;
// Based on http://stackoverflow.com/questions/1498658/modifying-a-string-in-resource-of-an-exe
// Modified
procedure UpdateResString(const AStringIdent: Integer; const ANewString: WideString);
var
ResData, TempData: TWordArray;
iSection, iIndexInSection: Integer;
i, iLen, iSkip, iPos: Integer;
begin
// Calculate the resource string area and the string index in that area
iSection := AStringIdent div 16 + 1;
iIndexInSection := AStringIdent mod 16;
ResData := ReadSectionCached(iSection);
// Calculate the position of the string
iLen := Length(ANewString);
iPos := 0;
for i := 0 to iIndexInSection do
begin
if iPos > High(ResData) then
begin
SetLength(ResData, iPos + 1);
ResData[iPos] := 0;
end;
if i <> iIndexInSection then
begin
iSkip := ResData[iPos] + 1;
Inc(iPos, iSkip);
end;
end;
// Put data behind strings into TempData
iSkip := 1{size} + ResData[iPos];
SetLength(TempData, Length(ResData) - (iPos + iSkip));
if Length(TempData) > 0 then
begin
CopyMemory(#TempData[0], #ResData[iPos + iSkip], Length(TempData)*SizeOf(TempData[0]));
end;
SetLength(ResData, iPos + (iLen + 1{size}) + Length(TempData));
// Overwrite string
ResData[iPos] := iLen;
Inc(iPos);
if iLen > 0 then
begin
CopyMemory(#ResData[iPos], #ANewString[1], iLen*SizeOf(ANewString[1]));
Inc(iPos, iLen);
end;
// Append TempData after our new string
if Length(TempData) > 0 then
begin
CopyMemory(#ResData[iPos], #TempData[0], Length(TempData)*SizeOf(TempData[0]));
end;
CacheSet(iSection, ResData);
end;
type
TGlobalData = record
GlobalPtr: Pointer;
Length: integer;
end;
function LoadResourcePtr(hModule: HMODULE; restype, resname: PChar; wIDLanguage: WORD): TGlobalData;
var
hFind, hRes: THandle;
begin
result.GlobalPtr := nil;
result.Length := -1;
hFind := Windows.FindResourceEx(hModule, restype, resname, wIDLanguage);
if hFind = 0 then RaiseLastOSError;
hres := Windows.LoadResource(hModule, hFind);
if hres = 0 then RaiseLastOSError;
result.GlobalPtr := Windows.LockResource(hres);
result.Length := Windows.SizeofResource(hModule, hFind);
end;
function _enumResLangsProc(hmodule: HMODULE; restype, resname: PChar; wIDLanguage: WORD;
lParam: LongInt): BOOL; stdcall;
var
rs: TGlobalData;
begin
rs := LoadResourcePtr(hmodule, restype, resname, wIDLanguage);
UpdateResource(lParam, restype, resname, wIDLanguage, rs.GlobalPtr, rs.Length);
result := true;
end;
function _enumResNamesProc(hmodule: HMODULE; restype, resname: PChar;
lParam: LongInt): BOOL; stdcall;
begin
EnumResourceLanguages(hmodule, restype, resname, #_enumResLangsProc, lParam);
result := true;
end;
function _enumResTypesProc(hmodule: HMODULE; restype: PChar;
lParam: LongInt): BOOL; stdcall;
begin
EnumResourceNames(hmodule, restype, #_enumResNamesProc, lParam);
result := true;
end;
{$R '..\dummydll\dummydll.RES'}
Then I use a wait form:
unit Wait;
interface
uses
...
type
TWaitForm = class(TForm)
...
end;
var
WaitForm: TWaitForm;
implementation
{$R *.dfm}
...
end;
The wait form will be called by dynamically showing the form:
procedure ShowWaitForm;
begin
...
{ I use my own _CreateForm function because it solves many workarounds for
juicy stuff like half-modal windows (which can be hidden without user action),
miscellaneous deadlocks etc. and to allow the form to be shown in a shared PAS file
without the requirement to add it to every DPR file where the WaitForm API is used. }
WaitForm := _CreateForm(TWaitForm, {Application.MainForm}AParent) as TWaitForm;
WaitForm.Show;
...
end;
function _CreateForm(InstanceClass: TCustomFormClass; AParent: TCustomForm): TCustomForm;
var
LOwner: TComponent;
begin
if Assigned(AParent) then
begin
LOwner := AParent;
end
else if Assigned(Application) then
begin
LOwner := Application;
end
else
begin
LOwner := nil;
end;
result := InstanceClass.Create(LOwner);
end;
The error message at 2% of the customers:
Resource TWaitForm was not found
However, other forms are working.
There are 2 theories I can think of:
1) Did the resource translation corrupt the DLL file / part of the RCData section? (Maybe a bug in the WinAPI's UpdateResource ?)
2) Is there a problem with the dynamic showing of the wait form (since other "static" forms are shown?)